1bw09ch17-ch18notes

# 1bw09ch17-ch18notes - Physics 1B schedule Winter 2009...

This preview shows pages 1–9. Sign up to view the full content.

Physics 1B schedule Winter 2009. Instructor: D.N. Basov [email protected] HW: Ch15: 1,10,11,13,15,17,20,24,27,28,30,32,36,38,43,46,48 Ch16: 1,3,5,8,12,15,19,22,23,25,29,31,33,35,43,45,47,49,60 Ch17: 1,3,8,9,11,13,16,19,20,23,31,33,39,45,52,60 Ch18: 1,3,5,7,13,17,21,26,31,33,35, Ch19: 1,3,8,9,11,15,19,22,24,27,29,34,37,38,41,44,47,49,57,61 Ch20: 1,5,8,11,13,16,18,23,25,27,29,31,34,37,39, Quizzes: Final exam: all material in ch 15-21 HW problems, problems in class, more… no make up final for any reason 4 best out of 5 No make-up quizzes for any reason OH: Fri 4-5pm, 6- 7pm Lecture: discussion of the final exam Lecture: AC circuits Lecture: Energy of the magnetic field 10: March 9 Quiz 5: chapter 20 Lecture Inductance, Inductors Lecture: Faraday’s law, Lenz’s law 9: March 2 Induced EMF Quiz 4: chapter 19 Lecture: current loop, solenoid 8: Feb 23 Lecture: torque on current loop, Ampere’s law Lecture: Magnetism University Holiday 7: Feb 16 Quiz 3: chapter 17-18 Lecture: RC circuits Lecture: Kirchhoff’s rules 6: Feb 9 Lecture: Resistors, series parallel Lecture: Resistivity, Electric power Lecture: Electric current, Ohm’s law 5: Feb 2 Quiz 2: chapter 16 Lecture: capacitor combinations Lecture: capacitance 4: Jan 26 Quiz 1: chapter 15 Lecture: Potential University Holiday 3: Jan 19 Lecture: Gauss law/examples Lecture: Electric Flux & Gauss’s law 2: Jan 12 Lecture: the Electric field Lecture: The Coulomb law, Lecture: Intro, 15.1-15.3 1:Jan 5 Friday Wed Mon Week T.A.: A: Zhoushen Huang [email protected] B: Andreas Stergiou, [email protected] Last update: Jan 30, 2009

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
17.1 Electric Current Chapter 15-16: electrostatics Chapter 17-18 charges in motion Electric current: the rate at which electric charge passes through a surface. q I t = + + + + Moving charges: positive, negative, both Direction of current: the direction of + charges flow! x V
17.1 Electric Current A flashlight bulb carries a current of 0.1 A. (a) Find the charge passed in 10 s. (b) How many electrons does this correspond to? 0.1(10) 1 q I t qI t C = ∆= = = (a) (b) 18 19 1 6.2 10 1.6 10 qN e q N x electrons ex = == =

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
17.2 Electric Current: a microscopic view 14 10 s τ Time between collisions Collisions of electron with the lattice (resistance) slows down the velocity. Drift velocity v d - average velocity in the direction of the flow.
Rate of flow is () arg arg d ch e ch e volume A x qn qnAv time volume time t ⎛⎞ == = ⎜⎟ ⎝⎠ d q I qnAv t A d x V t = V d –Drift velocity n – no. of charge carriers/volume q- charge per charge carrier 17.2 Electric Current: a microscopic view

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
17.2 Electric Current: a microscopic view 17.2 Find the drift velocity of electrons in Cu. For I=10 A, A=3x10 -6 m 2 . Use density of Cu, ρ =8.95 g/cm 3 (each atom of Cu contributes 1 carrier electron) M A =63.5g/mole d Iq n A v = qe = 23 66 28 3 6.0 10 (10 ) 8.95(10 ) 63.5 8.5 10 / A A N x n M nx e m ρ == = 19 28 6 10 1.6 10 (8.5 10 )(3 10 ) d d I v enA v xX X −− = = I v d 4 2.4 10 / d vx m s = M N N M density m atoms n A A = = = = / atom per mass 3
Electrons in a Resistor Lines of Electric Force (-Electric Field) Atoms of Resistor Material (e.g. Carbon) F= ma = qE

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
17.3 Current and voltage in circuits When a battery is placed in a
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 42

1bw09ch17-ch18notes - Physics 1B schedule Winter 2009...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online